Fact Sheet #14 – July 2004
Dr. Jack Desbiolles – Agricultural Machinery Research and Design Centre University of South Australia
Most farmers recognise the importance of seeding depth accuracy in maximising crop potential. However, being able to quantify the effect of a poorly set and operated
seeding machine on crop response is a useful step to justify efforts and investments to secure an optimum seeding depth.
Key points to consider
• Seeding depth uniformity is influenced by the seed placement quality within the furrow and the consistency of the added soil cover, both of which are influenced by a wide range of machinery factors. (figure 1.)
• Deep sowing (e.g., beyond 50-60mm) can significantly affect crop emergence and final grain yield.
• Many paddock situations can soon suffer a 5-10% yield loss as a result of inadequate seeding depth, with more extreme situations suggesting yield penalties of 15-20% or more.